I've noticed that ASE has a simple option that you can check to add an outline to the shader, but it doesn't appear to work when I apply the material / shader to a particle system. (Is there something unique or different about writing shaders for the particle system?)
Anyways, I also am trying to create the outline shader using nodes and as you can see still am not having any luck:
Can you please help me know what I need to do to get an outline effect working with a png texture in a particle system?
The reason I want to do it shader side is that when particles overlap, I want the outline to surround the entire group of particles and not have the outlines on each individual particle breaking up the effect. (If that makes sense)
Does amplify not support writing shaders that are compatible with particle systems?
It's definitely possible to create Particle shaders with ASE using the Template Shader feature, which is the ideal solution for custom shader pipeline requirements that take advantage of node-based shader authoring, although some shader knowledge is required.
Templates are just as regular Unity shaders but with special ASE tags placed at key points, be sure to check the official wiki page for additional information.
The current ASE package includes Particles, UI, Sprites and Image Effects templates that you can use as a starting point to develop your own custom shaders, you can find them at AmplifyShaderEditor \ Examples \ Official \TemplateExamples.